Internet Explorer usage continues to decline, losing somewhere between a tenth of a percent and half a percent each month to better browsers such as Firefox and Chrome. My prediction is that this is going to slow and eventually come to a stop. The problem is that there is a solid percent of internet users that have no idea what a brower is, and don't want to know, and will probably never learn. This block of users will never be persuaded by functionality or speed or new features.
In response to this inevitability, I propose people that write about or involve themselves in the Linux, or even in the general power user populous, stop supporting all versions of Internet Explorer immediately. I will admit that my website still has around 20-30% usage of Internet Explorer, but I am coming more and more to the opinion that those who continue to use it, probably wouldn't understand anything I'm writing about. This leads me to believe that this traffic ends up being people that are confused, as well as web spyders disguising themselves as a normal user, artificially inflating the numbers for IE.
Benefits of abandoning IE
By abandoning IE, it makes web development and testing easier. Development can focus on the standard DOM, and on leveraging some of the more advanced functionality of the web, such as new request types, as well as little things like rounded corners, or every-other CSS selectors.
Abandoning IE as a web developer or publisher is going to send a message to Microsoft and indirectly to uninformed users about their computing choices. When a percentage of the websites a person visits in a day stop working, they are going to ask why. If the answer is that their browser is broken (which it truly is), they will be much more likely to make a switch. The message it sends to Microsoft is that shipping a broken browser that is out of touch with the modern internet is going to hurt their users. This would also tell them that if they want to ship a working browser (which is what Apple and the open source community had to do in the past), they are going to have to adopt the features and usability of the other browsers, which in this case would be primarily based on standards and extensibility.
Problems with abandoning IE
By abandoning IE, you may make your website unusable for users that don't know, or can't upgrade (some corporate offices still require everyone to run IE6). This could also decrease your traffic. There is also a chance that Microsoft will just ignore any sites that do this, which is a definite probability based on their past behavior.
Summary and Philosophy
In theory by abandoning IE you will be able to focus on innovating for your best users, rather than hacking and making workarounds for your worst.